Several types of products for protecting conduits or wires from heat or abrasion, or both heat and abrasion, are known. In many applications the sleeve needs to be flexible to allow for installation over pipes or wires that are not straight or that may change shape during use. One exemplary application is protecting wires and piping around an internal combustion engine. One product for this use is sold by Federal-Mogul Systems Protection Group under the name Therm-L-Wrap. This product is formed from a woven fiberglass base layer with an outer layer of aluminum foil laminated to the fiberglass. The tube is slit lengthwise, and a flap coated with an adhesive extends from one edge of the slit to seal the seam once the sleeve has been place around the item to be protected and the opposite edges of the sleeves have been brought together. Another form of this sleeve is manufactured by folding an aluminum coated fiberglass strip in half lengthwise and stitching along the open edge. This sleeve and the previous one can open along the joined edges, resulting in a loss of protection. A third, more expensive, product by the same manufacturer is called Therm-L-Lite FG. This product uses a one-piece, substrate of fiberglass braided to form a tube with an outer layer of an aluminum heat-seal film adhesively bonded to it. This product is not vulnerable to coming open because it has no longitudinal seam, but it is more expensive than the previous two. A need remains in the market for sleeves that resist coming apart in use, that are equally or more effective at insulating from heat and/or abrasion and that are less expensive to manufacture.